World war I ended nearly 70 years ago but one battle is still being fought, you may not know this, to find and return thousands of pieces of stolen art and return them to their rightful owners. The men and women originally recruited for the battle are the subject of "The monuments men," a film opening Friday directed and starring George Clooney and the man right here, Matt Damon. You have been a great sport all day long here in the studio with us. We appreciate that. Well, thank you. I'm away from like my four crazy kids for a few minutes so I'll do anything. I'll serve coffee. Whatever you immediate. You can be hired. I do want to talk to you about "The monuments men." I watched it. I was just -- I learned so much. But, of course, all of us like you are so saddened by the passing, the death of Philip Seymour Hoffman and you had a chance to work with him in the talented Mr. Ripley. He had a way of just disappearing in roles. He was an actor's actor. He was one of the best actors to ever live without a doubt. Without a doubt and he was an even better person. He was a beautiful, beautiful person. And I know that all of us are continuing to think about him and his family. It's horrible. It's just horrible. And the fact that you are able to -- this is what's so great about film. You can transport us. You can make us forget our worries for a time and in "The monuments men," I was so glad that you admitted too that you weren't familiar with the history of them. Tell people why it's such an important story. Yeah, well, because what these guys did, they were kind of over the hill in soldiering terms and they were curators and art historians that basically formed this unit to go protect these cultural objects, these monuments and actually ended up going after all the stolen art that the nazis had looted from the european museums and from jewish collectors and these guys basically felt that art was worth their lives and some of them died doing this actually. But that art was really the center of our culture and what we really are and that's what this war was about. It was about -- that's exactly what we were fighting for and so it's a beautiful message and beautiful thing they did. The cast, they're not just unsung heroes, unlikely heroes. They were -- the last people that you would expect to see over there. Yeah, they were -- I think the oldest monuments men was in his late 60s and they had family, careers, very successful people in the art world who left all of that in order to contribute to, you know, their country in this really wonderful way. No, it's really -- it's sad actually, subsequently, you know, ten years ago when we went into Baghdad we didn't have these guys and it was a real tragedy actually That's a good point. I want to give everybody a little bit of a taste here. Your character is meeting cate Blanchett's character who is -- who is Parisian and she works in an art gallery there and you think you know French. Your character thinks you know French a little bit better than she lets on. Take a look. "The monuments men." Would you stop speaking in French or whatever language you're speaking. Well, if it weren't for us, you'd be speaking German. No, if it wasn't for you I might be dead. But I would still be speaking French. Oh, the cast was just as you said off the charts. Yeah, it was a really great great group. George Clooney wrote this and with grant heslov with his partner, they wrote it, produced it together. George directed it and starred in it. I mean, it was really -- it was one of the easiest jobs I've ever taken in the sense that I -- there was no question I was going to do it from the second it was offered to me to work with him and just at the level he's working at right now and then this group, it's bill Murray and John Goodman and these guys that I just watched for years and really admired and obviously had a chance to work with cate again, you know, it had been 16 years since we worked together. An important story but you were able to slip in humor there. It was -- you're just teaching us as we're sitting there watching. It's unbelievable that it has been made into a film. I agree. I was -- and I was amazed I didn't know the story. It's a really incredible story that's suited perfectly for a movie. I was kind of embarrassed, you know, I had that -- Yeah. Because I feel like I've read a lot about world war ii but never came across these guys. George directing. We hear you'll make your directing debut. Someday if I can take time away from all these kids, you know. Yeah, it's really a logistical issue for me, I like to be home so -- At home now is L.A. You left New York, you left this weather for the west coast. It's hard -- yeah, look, we're still adjusting to it. I mean I tried to, you know, I tried to make the most of L.A. So I went and got a mountain bike and started mountain biking and immediately broke my collarbone so I've been like laid up. But we miss New York. New York is going to be here. We'll be back someday, I know. So the kids have adjusted to -- They're doing great. They're doing great. You know, and obviously on days -- people complain about this weather but I grew up in this weather and I actually like it. You can stay. You can have it. You can have it let me tell you because you get to leave. That's why you like it so much. Hey, "The monuments men," thank you, thank you and George and the whole cast for bringing this to the attention of so many. It's very important. It's a great film. Thank you. All the best to you going forward and "Monuments men" opens nationwide on Friday.

This transcript has been automatically generated and may not be 100% accurate.

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